User`s manual

If you had chosen a wrong size, like an all tone of 8k, you would have obtained the
following analysis which clearly shows a lack of energy at alternating bins; the
effect is visible only at low frequency due to the logarithmic nature of the graph.
CLIO has the possibility of internal trigger (and relative delay) i.e. triggering with
respect of the generated signal thus obtaining a synchronous capture. As an
example let's see how a measurement presented in section 11.4 was done; please
refer to figures 11.9, 11.10 and 11.11. We have an acoustical measurement of a
tweeter, done stimulating it with a 2kHz 10ms tone burst (see 5.4.2 for details
about programming a bursted sinusoid); the FFT measurement is done using the
internal trigger; Fig. 11.9 shows the analysis and the captured time data that
clearly shows the flight time from the tweeter to the microphone, Fig. 11.9, Even if
the analysis is not our final target, it shows the power of synchronous acquisition
which permits the display of the arrival delay of sound to the microphone. To obtain
the desired result, as explained in 11.4, it is necessary to remove the flight time
plus the device settling time; this can be easily accomplished setting the internal
trigger delay, in FFT settings, to 1.5ms; the final result shown is shown in 11.11
9 FFT, RTA AND “LIVE” TRANSFER FUNCTION 105